The Sport Quattro's were very special, being around 12 inches shorter that the Ur Quattro for better handling on rally circuits. I like the open front end for airflow. The racing cars could produce 444 bhp from the inline 5. From the wiki:

"The Audi Sport Quattro was a Quattro programme car developed for homologation for Group B rallying in 1984, and sold as a production car in limited numbers.[1] It featured an all aluminium alloy 2,133 cc (130.2 cu in) (2.1 L) 20v DOHC engine slightly smaller than that of the Audi Quattro (in order to qualify for the 3-litre engine class after the scale factor applied to turbo engines). In road-going form the engine was capable of producing 225 kW (306 PS; 302 bhp),[1] with the competition cars initially producing around 331 kW (450 PS; 444 bhp).[1]"

Now in the process of making one, as a real one is unobtainable. More or less were going for the S1 style replica. found a full wide body kit from a company called pro speed, search pro speed S1 on youtube for a good time We are in search of any 5cyl 20vt wether its the 3b or AAN whatever we can get our hands on, as well as a 4000 quattro donor car. First steps will be shortening the car the 320mm (its close to that maybe not actual figure) followed by a complete floor swap from a 4000q to make it quattro. This will be a long project but we should be getting on it rather quickly.